{"id":"CVE-2026-49834","summary":"sigstore-go: Multi-log threshold bypass via single compromised log","details":"sigstore-go is a Go library for Sigstore signing and verification. Prior to 1.2.0, a verifier configured with WithTransparencyLog(N\u003e1) or WithSignedCertificateTimestamps(N\u003e1) counts verified witnesses per entry or per validation path rather than per log authority, allowing a single compromised transparency log or CT log to satisfy multi-log threshold requirements and defeat the multi-log policy. This issue is fixed in version 1.2.0.","aliases":["GHSA-9vcr-p3rj-q5q6","GO-2026-5952"],"modified":"2026-08-01T03:47:00.926750537Z","published":"2026-07-17T19:20:06.140Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-347"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49834.json"},"references":[{"type":"WEB","url":"https://github.com/sigstore/sigstore-go/releases/tag/v1.2.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49834.json"},{"type":"ADVISORY","url":"https://github.com/sigstore/sigstore-go/security/advisories/GHSA-9vcr-p3rj-q5q6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49834"},{"type":"FIX","url":"https://github.com/sigstore/sigstore-go/commit/dbb07e62623edd5b175fb9dd5a41dcb85a159207"},{"type":"FIX","url":"https://github.com/sigstore/sigstore-go/pull/633"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/sigstore/sigstore-go","events":[{"introduced":"0"},{"fixed":"8ca80c47ef03d26ebf174db7c296700b075b2c16"},{"fixed":"dbb07e62623edd5b175fb9dd5a41dcb85a159207"}],"database_specific":{"source":["CPE_RANGE","REFERENCES"],"cpe":"cpe:2.3:a:sigstore:sigstore-go:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"fixed":"1.2.0"}]}}],"versions":["v1.1.4","v1.1.3","v1.1.2","v1.1.1","v1.1.0","v1.0.0","v0.7.3","v0.7.2","v0.7.1","v0.7.0","v0.6.2","v0.6.1","v0.6.0","v0.5.1","v0.5.0","v0.4.0","v0.3.0","v0.2.0","v0.1.0"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-49834.json"}}],"schema_version":"1.8.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N"}]}